JP2016509123A - Cellulose-containing paint system - Google Patents

Abstract

The subject of the present invention is a) cellulose that is not chemically modified, and b) optionally polyolefin wax and / or Fischer-Tropsch wax and / or amide wax and / or bio-based wax, and c) film former. And d) optionally a solvent or water, and e) optionally a pigment, and f) optionally a volatile and / or non-volatile additive, wherein the chemical system Is a coating system as described above, wherein the unmodified cellulose has an average fiber length of 7 μm to 100 μm and an average aspect ratio of less than 5.

Description

  The present invention relates to a non-chemically modified cellulose-containing coating system to improve the deposition and redispersion behavior and to significantly improve the scratch resistance and feel, and the combination of cellulose / wax in the coating. Regarding use.

  According to DIN EN 971-1, a paint is generally understood to be a coating material having a predetermined characteristic image. As a coating material in liquid, pasty or powder form, paints have the problem of obtaining decorative properties, protective properties, in some cases, and special technical properties in accordance with standards. The paint can be classified according to the type of coating film forming agent (alkyd resin paint, acrylate resin paint, cellulose nitrate paint, epoxy resin paint, polyurethane resin paint, etc.), among others. According to the above criteria, the binder is defined as the pigment-free and filler-free part of the dried or cured coating part. Therefore, a binder is comprised from the non-volatile generating part of a coating-film formation agent and an additive. In general, paint systems that are not dried or uncured are coating film forming agents, such as epoxy resins, polyester resins, polyurethanes, cellulose derivatives, acrylic resins, etc., and in some cases, other components such as , Solvent, additive, filler and pigment. Solvent-free systems are customarily aqueous-based, for example used as dispersion paints, or are completely solvent-free. This is because the film-forming agent already exists in liquid form (eg, liquid monomer). In addition, additives are added to the paint system to adjust the desired usage characteristics. Thus, for example, micronized wax is added to impart to the paint surface resistance to scratching, matting, polishing, and resistance to metal marking (eg, Fette, Seifen, Anstrichmitel 87, Nr). 5, Site 214-216 (1985) (see Non-Patent Document 1). Similarly effective paint surface protection is obtained by adding certain silicones, which, like waxes, reduce the sliding friction coefficient of the dried paint, thereby reducing the so-called blocking (“blocking” in English). ”) And thereby improve scratch resistance (Ullmann's Encyclopedia of Industrial Chemistry, 5. Aflag, Vol. A 18, Kap. 4.3 Paints & Coe. 91 Paints & Coe. (See Non-Patent Document 2)). Scratch resistance can vary in the case of such paints and paint paint coatings exposed to mechanical stress, for example in the case of floors or furniture, such as writing desks, dining tables, etc. or children's toys. This is particularly important in the case of practical products. However, especially in the case of flooring materials, it plays a role not only in scratch resistance but also in ensuring the safety of the gait. Therefore, it is also important to reduce the risk of slipping, that is, to increase the sliding friction coefficient. It is. For everyday goods and furniture surfaces, a pleasant feel is often desired. In contrast to sliding friction and scratch resistance that can be quantified by measurement, feel can only be measured in quality. For the measurement of the touch, for example, concepts such as “softness (“ soft touch ”)”, velvety smoothness, smoothness, roughness, and hardness are used. The “soft touch / feel” effect is obtained directly by adding certain waxes or silicones to conventional paint systems, or via very soft polyurethane binders. At that time, the soft to smooth hand is often quite contrary to the required scratch resistance. Furthermore, in the case of coated wood surfaces, in particular the artificial and unnatural feel is often underestimated by the user. Instead, the painted surface is required to feel like natural wood.

  There is a constant demand on the market for painted surfaces with a soft and natural feel, combined with long-term durability, usually obtained by improved scratch resistance. In paint systems, it is difficult to combine both properties together.

  The use of cellulose in paints has so far been limited to cellulose derivatives. This is due to the fact that cellulose is completely insoluble in all common organic solvents, especially water. Therefore, so far, the use in paints is limited to cellulose derivatives (see BASF-Handbuch, Rackiertechnik, Vincentz-Verlag, 2002, Kap. Rhoffoffe, Site 45). In particular, cellulose nitrate and cellulose esters are described as additives in paint systems and as film formers. In that case, the cellulose can be modified with cellulose nitrate and acetate, propionate and butyrate with various degrees of esterification with organic and inorganic acids. Esters of cellulose with organic acids are particularly superior due to the improved light resistance and reduced flammability of cellulose nitrate. In addition, cellulose esters are characterized by improved heat resistance and cold resistance compared to cellulose nitrate, but are inferior in compatibility with other resins and organic solvents. In part, this drawback can be harmonized by the use of mixed esters.

  Cellulose-based fillers are conventionally used as methyl ether or ethyl ether to suppress the rheological properties of liquid paint systems. In contrast, the use of cellulose that has not been chemically modified in paints is not well known. Regarding this, for example, WO 2011/075837 pamphlet (Patent Document 1) describes nanocrystalline cellulose and silanized nanocrystalline cellulose for coating applications. Nanocrystalline cellulose (NCC) is obtained from purified cellulose, which is obtained by acid hydrolysis and subsequent dispersion, for example sonication. Cellulose fibers thus broken into individual fibers have a diameter of 5 to 70 nm and a length of 250 nm or less. However, in addition to the matte effect on the surface and a decrease in hydrophobic properties, a decrease in the scratch resistance of the polyurethane paint used is also observed due to the use of nanocrystalline cellulose. The effect cannot be compensated or overcompensated unless silanized, ie chemically modified, nanocrystalline cellulose is used.

  WO 2010/043397 (Patent Document 1) mentions the use of ultrafine cellulose as an additive for coating. Again, this is very fine cellulose particles having a diameter of 20 nm to 15 μm. The use of ultrafine cellulose provides a matte effect and increases the scratch resistance of the coated surface.

  Furthermore, cellulose-containing coating systems are unstable and tend to cure rapidly due to the insolubility of cellulose and the difference in density relative to the film former. This is especially true for low viscosity paint systems. The separation that occurs during storage of the paint system makes handling difficult. Deposits formed in a short time, especially consisting of cellulose, are very dense and difficult to redisperse.

International Publication No. 2010/043397 Pamphlet

Fette, Seifen, Anstrichmitel 87, Nr. 5, Site 214-216 (1985) 4. Ullmann's Encyclopedia of Industrial Chemistry, Auflag, Vol. A 18, Kap. 4.3 Paints & Coatings, Weinheim, 1991, Site 466 BASF-Handbuch, Lackiertechnik, Vincentz-Verlag, 2002, Kap. Rohmstoffe, Site 45 4. Ullmann's Encyclopedia of Industrial Chemistry, Auflag, Vol. A 18, Kap. Paints & Coatings, Weinheim, 1991, Site 368ff BASF-Handbuch, Lackiertechnik, Vincentz-Verlag, 2002, Kap. Rohmstoffe, Site 28ff BASF-Handbuch, Lackiertechnik, Vincentz-Verlag, 2002, Kap. Rohmstoffe, Site 26 4. Ullmann's Encyclopedia of Industrial Chemistry, Auflag, Vol. A 18, Paints & Coatings, Kap. 2.10, Weinheim, 1991, Site 407-412 4. Ullmann's Encyclopedia of Industrial Chemistry, Auflag, Vol. A 18, Paints & Coatings, Kap. 2.9, Weinheim, 1991, Site 403-407 4. Ullmann's Encyclopedia of Industrial Chemistry, Auflag, Vol. A 18, Paints & Coatings, Kap. 2.6 & 2.7, Weinheim, 1991, Site 395-403. 4. Ullmann's Encyclopedia of Industrial Chemistry, Auflag, Vol. A 18, Paints & Coatings, Kap. 2.6, Weinheim, 1991, Site 389-395 4. Ullmann's Encyclopedia of Industrial Chemistry, Auflag, Vol. A 18, Paints & Coatings, Kap. 2.2, Weinheim, 1991, Site 369-374 4. Ullmann's Encyclopedia of Industrial Chemistry, Auflag, Vol. A 5, Weinheim 1986, Kap. Cellulose, Site 375 ff. 4. Ullmann's Encyclopedia of Industrial Chemistry, Auflag, Vol. A 28, Weinheim 1996 in Kapitel 6.1.1. /6.1.2. (Hochduckpolymerization, (Wachse), Kapitel 6.1.2. (Ziegler-Natta-Polymerization, Polymerization Mit Metalocatalysatoren) soie Kapiteer. 4. Ullmann's Encyclopedia of Industrial Chemistry, Auflag, Vol. A 28, Weinheim 1996, Kapitel 6.1.5 4. Ullmann's Encyclopedia of Industrial Chemistry, Auflag, Vol. A 28, Weinheim 1996 in Kapitel (Wachse) 4. Ullmann's Encyclopedia of Industrial Chemistry, Auflag, Vol. A 28, Weinheim 1996, Kapitel. (Wachse)

  There are serious drawbacks to introducing unmodified cellulose into the coating system as an additive component and therefore there is a need to overcome these disadvantages.

  Surprisingly, a paint system using chemically unmodified cellulose having a predetermined average fiber length and a predetermined average aspect ratio is soft and has a natural feel and Show improved coating scratch resistance and in combination with polyethylene waxes and / or Fischer-Tropsch waxes and / or amide waxes and / or bio-based waxes give an unpredictable stability of the coating formation against deposition It was found that

  Furthermore, the use of this combination surprisingly significantly improves the scratch resistance.

Therefore, the subject of the present invention is
a) unmodified chemically cellulose, and b) optionally polyolefin wax and / or Fischer-Tropsch wax and / or amide wax and / or biobase wax, and c) film former, and d) optionally Solvent or water, and e) optionally pigments, and
f) optionally, volatile and / or non-volatile additives,
In which the unmodified cellulose has an average fiber length of 7 μm to 100 μm, preferably 15 μm to 100 μm, particularly preferably 15 μm to 50 μm, and an average aspect ratio of less than 5 The coating system as described above.

  A further subject of the present invention is a method for improving the deposition and redispersion behavior and scratch resistance of a paint system, which comprises one or more polyolefin waxes and / or Fischer-Tropsch waxes and / or Or an amide wax and / or a bio-based wax and a non-chemically modified cellulose having an average fiber length of 7 μm to 100 μm, preferably 15 μm to 100 μm, particularly preferably 15 μm to 50 μm, and an average aspect ratio of less than 5 It is this method characterized by adding. The paint system can further contain pigments and solvents or water, and other volatile and / or non-volatile additives.

  A coating without addition of cellulose by adding chemically unmodified cellulose having an average fiber length of 7 μm to 100 μm, preferably 15 μm to 100 μm, particularly preferably 15 μm to 50 μm, and an average aspect ratio of less than 5; In comparison, since the scratch resistance and feel of the coating film can be improved, the present invention further provides a method for improving the scratch resistance of the coating film (cured coating system) and a method for achieving a soft feel. However, the process also comprises using the coating system with chemically unmodified cellulose having an average fiber length of 7 μm to 100 μm, preferably 15 μm to 100 μm, particularly preferably 15 μm to 50 μm, and an average aspect ratio of less than 5. It is characterized by adding to.

  The coating system described above can further contain pigments and solvents or water, as well as other volatile and / or non-volatile additives.

  In principle, all suitable materials as pigments, film formers, auxiliaries and solvents, for example, Ullmann's Encyclopedia of Industrial Chemistry, 5. Auflag, Vol. A 18, Kap. Paints & Coatings, Weinheim, 1991, Site 368ff (Non-Patent Document 4), or BASF-Handbuch, Rackiertechnik, Vincentz-Verlag, 2002, Kap. Examples include those disclosed in Rohmstoff, Site 28ff (Non-patent Document 5).

  The binder should be understood to be a pigment-free part and a filler-free part of the dried or cured coating, similar to DIN 971-1. These contain other non-volatile additives in addition to the film former. A coating is to be understood as a cured or dried paint system. (See BASF-Handbuch, Rackiertechnik, Vincentz-Verlag, 2002, Kap. Roffstoffe, Site 26 (Non-Patent Document 6)).

  As the film-forming agent, according to the present invention, both polyurethane-based and epoxy-based resins are suitable, both in one-component form and two-component form. Further suitable film formers other than cellulose derivatives such as cellulose nitrate and cellulose esters are alkyd resins and acrylate based systems such as polymethyl methacrylate.

  Epoxy-based film formers are polyaddition resins, which are at least difunctional epoxy-containing monomers such as bisphenol-A-bisglycidyl ether, hexahydrophthalic acid-diglycidate, etc., or prepolymers or It crosslinks by binding to another reaction partner (curing agent) via a macromonomer.

  Therefore, they are usually processed as two-component resins. Typical curing agents are amines, acid anhydrides or carboxylic acids. As amines, aliphatic diamines such as ethylene diamine, diethylene triamine, triethylene tetraamine and the like, as well as cyclic aliphatic amines such as isophorone diamine, or aromatic diamines such as 1,3-diaminobenzene are often used. The As the acid anhydride, for example, phthalic anhydride or diester of trimellitic anhydride is used. Such epoxy-based film formers and their use in paints, as well as suitable solvent-based, solvent-free, and water-based embodiments are described in Ullmann's Encyclopedia of Industrial Chemistry, 5. Auflag, Vol. A 18, Paints & Coatings, Kap. 2.10, Weinheim, 1991, Site 407-412 (Non-patent Document 7).

  Polyurethane-based film formers are also polyaddition resins, which are brought about by reacting from isocyanate-containing monomers in combination with polyhydric alcohols. Depending on the chemical composition of the resin, it is classified into one-component PU paint and two-component PU paint. Typical isocyanate-containing monomers include, for example, toluene diisocyanate (TDI) and diphenylmethane diisocyanate (MDI), polymeric diphenylmethane diisocyanate (PMDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate. Based on Narto (IPDI). Polyols are typically used in various complexities as polyesters, acrylic acid copolymers and polyether polyols. PU resins are utilized as solvent-containing, solvent-free or water-based systems. Details of PU resins for paints can be found in Ullmann's Encyclopedia of Industrial Chemistry, 5. Auflag, Vol. A 18, Paints & Coatings, Kap. 2.9, Weinheim, 1991, Site 403-407 (Non-patent Document 8).

  Polyesters are divided into saturated polyester binders and unsaturated polyester binders. Polyester binders are polyvalent carboxylic acids such as terephthalic acid, isophthalic acid, trimellitic acid, adipic acid, sebacic acid, dimer fatty acids and the like, and polyols such as ethylene glycol, diethylene glycol, glycerin, butanediol, hexanediol. , Trimethylolpropane and the like. Depending on the rigidity of the diacid and polyol, the soft to hard mechanical properties can be adjusted. Unsaturated polyesters can additionally utilize polymerizable vinyl groups that can be crosslinked by UV light or radical initiators. Polyesters for paints can be found in Ullmann's Encyclopedia of Industrial Chemistry, 5. Auflag, Vol. A 18, Paints & Coatings, Kap. 2.6 & 2.7, Weinheim, 1991, Site 395-403 (Non-Patent Document 9).

  Alkyd resins belong to the group of polyesters. These can be classified into an air drying system and a furnace drying system according to the drying mechanism. Chemically alkyd resins include polyhydric alcohols such as glycerin, pentaerythritol, polyhydric acids such as phthalic acid, phthalic anhydride, terephthalic acid and the like, oils or unsaturated fatty acids such as linoleic acid, It is formed by reacting in the presence of oil acid or the like. In most cases, the alkyd resin is a crosslinking accelerating catalyst and a so-called desiccant is added. Alkyd resins and embodiments thereof are described, for example, in Ullmann's Encyclopedia of Industrial Chemistry, 5. Auflag, Vol. A 18, Paints & Coatings, Kap. 2.6, Weinheim, 1991, Site 389-395 (Non-Patent Document 10).

  The most important film formers based on cellulose include cellulose nitrate and cellulose esters such as cellulose acetate, cellulose acetate butyrate and cellulose acetate propionate. The raw material for the corresponding cellulose derivative is purified natural cellulose, which is often taken directly from the tree. Derivatizing agents are, for example, nitrating acid as well as acid anhydrides, such as acetic acid, propionic acid, butyric acid. In contrast to cellulose that has not been chemically treated, cellulose derivatives are soluble in organic solvents, in particular in acetone and in ethyl acetate. 4. Cellulose derivative-film forming agent is described in Ullmann's Encyclopedia of Industrial Chemistry, 5. Auflag, Vol. A 18, Paints & Coatings, Kap. 2.2, Weinheim, 1991, Site 369-374 (Non-patent Document 11).

  Cellulose is of particular interest industrially because it is very readily available. Cellulose is also the most abundant polysaccharide because it is the most abundant organic compound in nature. As a renewable raw material, about 50% by weight of cellulose is a major component of the plant cell wall. Cellulose is a polymer composed of monomeric glucose, which is linked through β-1,4-glycosidic bonds and consists of hundreds to thousands of repeating units. The glucose molecules in cellulose are each twisted 180 ° relative to each other. Thereby, unlike for example glucose polymer starch, the polymer takes a linear form. The industrial use of cellulose as a raw material for the chemical industry is diverse. The material utilization in that case includes use as a raw material for paper and use for production of clothing. The main cellulose sources used are wood and cotton.

  In the case of wood, cellulose exists primarily in the form of microcrystalline microfibers, which bind via H-bonds to form macrofibers. In combination with hemicellulose and lignin, they form the cell wall of the plant.

Cellulose is industrially produced from wood by various cell degradation methods. In these methods, lignin and hemicellulose are degraded and dissolved. Chemical decomposition methods are classified into a sulfate method (alkali method) and a sulfite method (acid method). In the case of the sulfite method, for example, wood chips are decomposed with water and sulfur dioxide (SO ₂ ) at elevated pressure and elevated temperature. In this method, sulfonation cleaves lignin and converts it to lignin sulfonic acid, which becomes a water-soluble salt, which can be easily removed from the fiber. The hemicellulose present is present in the wood depending on the pH value and is converted to sugar by acid hydrolysis. The cellulose obtained from this process can then be further chemically modified or derived. Alternatively, a filler that has not been chemically treated can be obtained after washing. Other less important decomposition methods are based on mechanical and thermomechanical decomposition methods, and chemical thermomechanical decomposition methods.

  In the sense of the present invention, the cellulose is not chemically modified during these decomposition processes. 4. Ullmann's Encyclopedia of Industrial Chemistry, Auflag, Vol. A 5, Weinheim 1986, Kap. Cellulose, Site 375 ff. (Non-Patent Document 12) has a detailed description of cellulose.

  Suitably in the meaning of the present invention, the chemically unmodified cellulose has a particle size having a D99-value measured using laser diffraction of ≦ 100 μm, preferably ≦ 50 μm. The D99-value indicates the maximum particle size present in the particle mixture. Suitable cellulose powders can also be obtained in some cases by separating, for example screening or sieving, or micronizing coarse cellulose. Cellulose is from Ullmann's Encyclopedia of Industrial Chemistry, 5. Auflag, Vol. A 5, Weinheim 1986, Kap. Cellulose, Site 375 ff. (Non-Patent Document 12).

  Non-chemically modified cellulose is used in an amount of 0.1 to 12% by weight, preferably 0.2 to 6% by weight, particularly preferably 1.0 to 2.0% by weight, based on the coating system. The

  As the wax component, synthetic hydrocarbon waxes such as polyolefin waxes are suitable. These can be produced by thermal decomposition of branched or unbranched polyolefin plastics or by direct polymerization of olefins. Polymerization methods include, for example, radical methods, in which an olefin, generally ethylene, is converted to a more or less branched polymer chain at high pressure and temperature, which is then converted to ethylene and / or higher 1- In the case of olefins such as propylene, 1 butene, 1-hexene, etc., it is considered to polymerize to unbranched or branched waxes using organometallic catalysts such as Ziegler-Natta catalysts or metallocene catalysts. . Suitable methods for producing olefin homopolymer waxes and olefin copolymer waxes are described, for example, in Ullmann's Encyclopedia of Industrial Chemistry, 5. Auflag, Vol. A 28, Weinheim 1996 in Kapitel 6.1.1. /6.1.2. (Hochduckpolymerization, (Wachse), Kapitel 6.1.2. (Ziegler-Natta-Polymerization, Polymerization Mita- valentcatalysatoren) (Non-patent document).

  Furthermore, so-called Fischer-Tropsch wax can be used. It is produced catalytically from synthesis gas and is classified as a polyethylene wax by a lower average molar mass, a narrower molar mass distribution and a lower melt viscosity.

  The hydrocarbon waxes used can be non-functional or functional with polar groups. The introduction of such polar functionality may be achieved by appropriately modifying non-polar waxes, for example by oxidation with air, or polar olefin monomers such as α, β-unsaturated carboxylic acids and / or their This can be done by grafting derivatives such as acrylic acid or maleic anhydride. In addition, polar waxes can be made by copolymerization of ethylene with polar comonomers, such as vinyl acetate or acrylic acid, and can also be made by oxidative degradation of high molecular weight non-wax ethylene homopolymers and ethylene copolymers. . Corresponding examples include, for example, Ullmann's Encyclopedia of Industrial Chemistry, 5. Auflag, Vol. A 28, Weinheim 1996, Kapitel 6.1.5 (Non-Patent Document 14).

Suitable polar waxes are further amide waxes, for example long chain carboxylic acids such as fatty acids can be obtained by reaction with mono- or polyvalent amines. The fatty acids typically used for this have a chain length in the range of 12 to 24, preferably 16 to 22, C-atoms and may be saturated or unsaturated. The fatty acids preferably used are C ₁₆ -and C ₁₈ -acids, in particular palmitic acid and stearic acid, or a mixture of both acids. As the amine, in addition to ammonia, in particular, a polyvalent, for example, divalent organic amine can be mentioned, and in this case, ethylenediamine is preferable. Particular preference is given to the use of a wax made from industrial stearic acid and ethylenediamine, which is commercially available under the name EBS-wax (ethylenebisstearoyldiamide).

  In addition, a bio-based wax can be used, in which case it is usually a polar ester wax. In general, bio-based wax is understood as a wax based on renewable raw materials. In this case, natural ester wax or chemically modified ester wax can be used. Typical natural biobased waxes are, for example, Ullmann's Encyclopedia of Industrial Chemistry, 5. Auflag, Vol. A 28, Weinheim 1996 in Kapitel (Wachse) (Non-Patent Document 15). These include palm waxes such as carnauba wax, plant waxes such as candelilla wax, sugar cane wax and straw wallse, beeswax, rice wax and the like. Chemically modified waxes are often produced from vegetable oil based fatty acids by esterification, transesterification, amidation, hydrogenation, and the like. For example, a metathesis product of vegetable oils corresponds to this.

  Bio-based waxes also further include montan wax either in unmodified or purified or derived form. A detailed description of such waxes can be found, for example, in Ullmann's Encyclopedia of Industrial Chemistry, 5. Auflag, Vol. A 28, Weinheim 1996, Kapitel. (Wachse) (Non-Patent Document 16).

  There are various ways to incorporate wax into the coating system. For example, the wax is dissolved at high temperature in a solvent, and subsequent cooling yields a finely divided, liquid dispersion or pasty thick substance that is mixed with the paint system. Furthermore, it is possible to grind the wax in the presence of a solvent. According to one of the widespread techniques, wax is also incorporated into the paint formulation as a fine powder solid form ("micronized"). The fine powder is produced, for example, by grinding in an air jet mill or by spraying. The average particle size (D50 or intermediate value) of such powders is generally in the range of 5-15 μm. The D99-value of the wax micronization used is at most 100 μm, preferably at most 60 μm, particularly preferably at most 50 μm. The precondition for making the finely pulverized product pulverizable is to prevent the hardness and brittleness of the wax product from becoming too low.

  The wax is used in an amount of 0.1 to 12.0% by weight, preferably 0.2 to 6.0% by weight, particularly preferably 1.0 to 2.0% by weight, based on the coating system.

  Non-chemically modified cellulose can be dispersed before or after adding wax to the coating system, or added together by introducing a mixture of micronized wax and unmodified cellulose. Can do. It has been found to be particularly advantageous to micronize unmodified cellulose and / or wax together and to charge them as a micronized mixture. The micronized mixture can also be dispersed before or after the addition of the printing ink system. Dispersion methods are known to the person skilled in the art, and here generally high speed stirrers or mixers are used, for example Mizer disks or dissolver disks.

  In a combination of polyolefin waxes and / or Fischer-Tropsch waxes and / or amide waxes and / or bio-based waxes, the chemically unmodified cellulose shows a reduced deposition tendency in the liquid paint system and the sediment deposited Can be easily redispersed. In addition, the cured paint exhibits significant scratch resistance.

  The coating system of the present invention comprises volatile and non-volatile additives such as plasticizers, crosslinking agents, crosslinking accelerators, UV stabilizers, antioxidants, surfactants, wetting agents, defoamers, thixotropic aids. Agents and other auxiliaries can be included in conventional addition concentrations.

  The paint system of the present invention is particularly suitable for painting wood paints, especially wooden furniture, wooden flooring and all types of wooden articles. By using cellulose that has not been chemically modified within the scope of the present invention, a natural texture (feel) of wood tone can be obtained as compared with a paint that does not use cellulose.

  The following examples illustrate the invention in more detail, but do not limit the invention.

Performance Test Arbocel UFC M 8, Arbocel BE 600-30 PU and Arbocel BWW 40 were used as raw materials for the unmodified cellulose of the present invention. As a comparative substance, corn starch particles (manufacturer, Roquette GmbH) separated by sieving with respect to particle size were used. Thus, in particular, different particle size distributions could be tested. Arbocel species were similarly classified with respect to their particle size distribution.

The following commercial product from the product of Clariant Product (Deutschland) GmbH was used as the wax:
-Ceridust 2051: micronized Fischer-Tropsch wax; D99 <50 μm
Ceridust 3620: micronized polyethylene wax; D99 <50 μm
-Ceridust 5551: micronized montan wax; D99 <50 μm

  Characteristic particle sizes D50, D90 and D99 were measured based on laser diffraction measurements using a Mastersizer 2000 (Malvern) according to ISO 13320-1. To that end, the sample was pretreated using a dry dispersion apparatus (Sirocco 2000).

Measurement of Scratch Resistance To measure scratch resistance, the coating system to be tested was applied on a glass surface and tested with an Erichsen hardness test rod (TYP 318). The scratch resistance was measured according to DIN ISO 1518 using the hardness test rod and a Bosch grinder with a diameter of 0.75 mm. Scratch marks are about 10 mm long and leave clear marks on the paint. Different forces can be applied to the paint surface by adjusting the tension of the spring. The force required to leave a clear trace on the paint was measured for various paint formulations.

Judgment of touch The touch of each paint surface was judged by rubbing with the back of the hand. In addition, 20 judges were used to obtain individual opinions. The judgment in the table note corresponds to the majority of opinions.

Measurement of Sliding Friction Coefficient According to ASTM-Method D2534, the sliding friction coefficient was measured using a Friction-Pel Tester, Model 225-1 manufactured by Thwing-Albert Instruments Company. For this, a glass plate coated with the paint to be tested was applied to the analyzer. Subsequently, a metal slide (349 g) covered with leather was placed on the coated surface. The slide was then pulled over the coated glass surface with a constant measure (15 cm / min). The force required to pull the slide was measured. Since the dynamic coefficient of sliding friction was measured, the initial force required to move the slide was negligible.

Test of deposition behavior and re-dispersion behavior In a graduated cylinder, 4 g of each sample to be tested was dispersed in 200 g of polyurethane paint (2 K PUR) containing two-component solvent and 200 g of butyl acetate, and the dispersion was allowed to stand. After a predetermined time interval, the thickness of the deposited sediment layer was read. The smaller the measured value, the higher the density of the deposited sediment. The redispersibility of the precipitate was tested by carefully shaking the graduated cylinder. The results are shown in Table 2.

  Table 2 shows that the higher the thickness of the precipitate, the better the particles can be redispersed. Natural corn starch forms a dense precipitate in both systems, which is difficult to redisperse. The powder mixture consisting of natural cellulose, Arbocel BE600-30 PU and polyethylene wax showed a clearly reduced deposition tendency and best redispersibility in both systems. The natural cellulose, Arbocel BE600-30 PU alone, showed an improved tendency to deposit as well. The paint in 2K PUR could hardly be redispersed, whereas it could be redispersed without problems in butyl acetate.

Tests in two-component polyurethane paints based on solvents The PUR paint used had the following composition:
Formula:
Ingredient 1
Desmophen 1300 (75% concentration in xylene) 32.0% by weight
Walsroder Nitrocellulose E 510 (in 20% ESO)
1.5% by weight
Acronal 4 L (10% concentration in ethyl acetate) 0.2% by weight
Baysilone OL 17 (10% concentration in xylene) 0.2% by weight
Ethyl acetate 10.4% by weight
Butyl acetate 11.0% by weight
Methoxypropyl acetate 1 0.8% by weight
Xylene 8.9% by weight
75.0% by weight

Ingredient 2
Desmodur IL 14.2% by weight
Desmodur L 75 9.4 wt%
Xylene 1.4% by weight
25.0% by weight

  The above paint system is mixed with 2% or 4% of a micronizer (wax or cellulose or wax / cellulose mixture) and applied onto the glass surface using a doctor blade (60 μm). Scratch resistance as well as sliding friction coefficient can be measured after 24 hours of drying time and subsequent storage for 24 hours in an air conditioned room.

  The values are shown in Table 3.

  The polyurethane paint has a scratch resistance of 0.1 N, which is a very low value (Example 3). With the addition of Arboceltype Arbocel UFC M8 and Arbocel BE 600-30 PU (Examples 22-25), very enhanced scratch resistance could be obtained. In particular, due to the addition of Arbocel BE 600-30 PU (Examples 24 and 25), the scratch resistance of the paint used is greatly enhanced. With the introduction of the wax / cellulose mixture (Examples 12 to 15), the scratch resistance of the coating system is further enhanced.

  Addition of cellulose having a predetermined fiber length and a predetermined aspect ratio, which are not chemically modified, to the coating system has a favorable effect on the hand. The paint systems described in Examples 22 and 23 both contain Arbocel UFC M8 as an additive component and are characterized by a very soft feel. On the other hand, when Arbocel BE 600-30 was added, it showed a natural feel of wood.

  When a mixture of cellulose and wax is added to the coating system (Examples 12 to 15), the touch of the obtained coating film corresponds to the corresponding cellulose-containing coating. Furthermore, the mixture consisting of cellulose and wax significantly improves the scratch resistance as described above, so that, in particular in Examples 14 and 15, the very high scratch resistance can be achieved with a natural wooden feel. I was able to get it in combination.

  Arbocel BWW 40 was not tested in combination with wax because it could not be applied without problems due to the size of the cellulose particles. Even when 4% Arbocel BWW 40 (Example 27) was used, the value for scratch resistance could not be measured. This is because the paint surface was very heterogeneous.

  By adding the micronized wax to the paint system described above, scratch resistance increased as desired was obtained by reducing the sliding friction coefficient (Examples 8-15). This is undesirable, for example, when coating floor finishes.

  By adding unmodified cellulose to the coating system, scratch resistance is increased with only a slight reduction in the coefficient of sliding friction (Examples 26-29). This favorable effect is also obtained when cellulose that has not been chemically modified is combined with micronized wax (Examples 16-19).

Tests in water-based polyurethane paints:

  The PUR paint used has the following composition.

Formula Bayhydr UH 2342 89.0 wt%
Demineralized water 3.0% by weight
Dipropylene glycol dimethyl ether 3.0% by weight
BYK 028 0.8% by weight
BYK 347 0.5 wt%
Schwego Pur 6750 (5% concentration in water) 1.5% by weight
100.0% by weight

  This paint system was also mixed with 2% or 4% micronizer and applied onto the glass surface with a doctor blade (60 μm). After 24 hours of drying time and subsequent storage for 24 hours in the air-conditioned room, the scratch resistance and the coefficient of sliding friction could be measured. Values are shown in Table 4.

  By adding Arbocel UFC M8 and Arbocel BE 600-30 PU to the above paint system (Examples 47-50), the scratch resistance could be increased. The feel of the resulting paint system varies depending on the size of the cellulose-micronized product used. The somewhat coarser type Arbocel BE 600-30 PU provided a natural wood feel. The combination of Arbocel and wax showed the best results with respect to scratch resistance. The feel of the paint to which the mixture of cellulose fines and wax fines was added was comparable when modified by the single addition of Arbocel species. The combination of wax micronizer as well as cellulose micronizer could provide a natural wood feel to the coating system in combination with increased scratch resistance.

  Arbocel BWW 40 was not tested in this system in combination with wax because it caused problems during application due to the size of the cellulose particles. As with the solvent-based system, for the 4 percent concentration of Arbocel BWW 40 (Example 52), the value for scratch resistance could not be measured because the paint surface was very heterogeneous.

  By adding cellulose that has not been chemically modified to the above coating system, scratch resistance is increased with only a slight reduction in the coefficient of sliding friction (Examples 51-54). This favorable effect is also obtained when cellulose that has not been chemically modified is combined with finely divided wax (Examples 41 to 44).

Tests on water-based acrylic paints:

  The acrylic paint used had the following composition.

Formulation Part 1 i) Viacryl VSC 6295w / 45WA 88.5 wt%
ii) butyl glycol 3.8% by weight
iii) Ethyl diglycol 2.0% by weight
iv) Demineralized water 4.0% by weight

Part 2 i) Coatex BR 100 (Thickener) 0.4 wt%
ii) Surfynol DF 110 0.5% by weight
iii) BYK 348 0.2% by weight

Part 3 i) BYK 347 0.2 wt%
ii) BYK 380 N 0.4 wt%
100.0% by weight

The first part was stirred at about 1500 rpm for about 10 minutes with the production dissolver. Subsequently, the ingredients of Part 2 were added individually and sequentially and dispersed for 10 minutes at about 2000 revolutions / minute. The third part was added to the dissolver at about 1000 rpm. Finally, wax, cellulose or starch (2% and 4%) were incorporated at 1500 revolutions / minute with a stirring time of 20 minutes.

  After the preparation, the paint was similarly applied on the glass surface using a doctor blade (60 μm). After 24 hours of drying time and subsequent storage for 24 hours in the air-conditioned room, the scratch resistance and coefficient of sliding friction could be measured.

Claims (10)

a) unmodified chemically cellulose, and b) optionally polyolefin wax and / or Fischer-Tropsch wax and / or amide wax and / or biobase wax, and c) film former, and d) optionally Solvent or water, and e) optionally pigments, and
f) optionally, volatile and / or non-volatile additives,
A coating system as described above, wherein the cellulose not chemically modified has an average fiber length of 7 μm to 100 μm and an average aspect ratio of less than 5.   2. A paint system according to claim 1, characterized in that the chemically unmodified cellulose is used in an amount of 0.1 to 12.0% by weight with respect to the paint system.   Coating system according to claim 1 or 2, characterized in that the wax is used in an amount of 0.1 to 12% by weight with respect to the coating system.   2. Coating system according to claim 1, characterized in that the polyolefin wax or Fischer-Tropsch wax or amide wax or biobase wax is used in finely divided form with a D99 value of up to 100 [mu] m.   Film forming agents from the group of epoxy resins (one or two components), polyurethane (one or two components), acrylic resins, cellulose derivatives, in particular cellulose nitrate and cellulose esters, or from alkyd resins The coating system according to any one of claims 1 to 3, characterized in that is used.   A method for improving the feel and scratch resistance of a paint system, comprising adding to the paint system chemically unmodified cellulose having an average fiber length of 7 μm to 100 μm and an average aspect ratio of ≦ 5 Characterized by the above.   A method for improving the deposition and redispersion behavior and the hand and scratch resistance of a paint system, said polyolefin system and / or Fischer-Tropsch wax and / or amide wax and / or biobase wax in the paint system, and Process as described above, characterized in that an unmodified chemically cellulose having an average fiber length of 7 μm to 100 μm and an average aspect ratio of less than 5 is mixed.   8. Process according to claims 6 and 7, characterized in that the unmodified cellulose is used in an amount of 0.1 to 12.0% by weight with respect to the paint system.   9. Process according to claims 7 and 8, characterized in that the wax is used in an amount of 0.1 to 12.0% by weight with respect to the paint system.   The coating system of the present invention is a conventional addition such as crosslinking agents, crosslinking accelerators, flow control aids, wetting agents, defoaming agents, plasticizers, pigments, UV stabilizers, antioxidants and other auxiliaries. Use according to claims 1 to 9, characterized in that it is used with an agent.